MTP: took 2.5 minutes and a 40 second DB refresh
UMS: 40 seconds and DB refresh time of 1 minute aprox.

How I did the change using win 7?

a) go to control panel and choose device manager
b) under portable devices, click the '+' to expand and right click WALKMAN and choose Update Driver.
c) Click on Browse My computer for Driver Software
d) Click on Let me Pick from a List of Drivers on my computer
e) Click on the UMS or USB driver and you're done!
* I recommend that you first click uninstall on the right click-menu to unistall the MTP driver.

Correct AFAIK, defragging a flash drive will not give you any performance benefits. Since there's no head to move like on HD, there's no additional time in fetching data from a flash drive. It doesn't matter how the files are laid out, it's all just as fast.

Edit: Also writing to flash memory causes it to degrade ever so slightly, reading does not, so the more you write to a flash device the shorter its lifespan will be. So if you're regularly defragging a flash drive, you are adding thousands of write operations each time you do so and shorting the life of it.

MTP: took 2.5 minutes and a 40 second DB refresh
UMS: 40 seconds and DB refresh time of 1 minute aprox.

How I did the change using win 7?

a) go to control panel and choose device manager
b) under portable devices, click the '+' to expand and right click WALKMAN and choose Update Driver.
c) Click on Browse My computer for Driver Software
d) Click on Let me Pick from a List of Drivers on my computer
e) Click on the UMS or USB driver and you're done!
* I recommend that you first click uninstall on the right click-menu to unistall the MTP driver.

This sounds promising - I've been very disgusted with how slow my walkman is when interacting with my computer.